Yellow fever vaccination coverage among nomadic populations in Savannah region, Ghana; a cross-sectional study following an outbreak

Abstract

AbstractYellow fever (YF) is a viral infection transmitted via mosquito bites. The disease is endemic in many African countries and Ghana has experienced frequent outbreaks. Vaccine coverage is often low in nomadic communities.ObjectiveTo evaluate YF vaccination coverage among nomadic population after the YF vaccination campaign in targeted communities in the Savanah region, Ghana.Study DesignA community-based cross-sectional study, with a modified WHO vaccination coverage cluster survey was used to collect data from 2914 nomads in 414 nomadic households across 22 YF affected communities. Data were analyzed using Stata version 15. T-test analysis of variance was conducted to determine the statistical difference among different population groups.ResultsOut of the 2914 household members surveyed, 2342 (80%) were vaccinated against YF. There was a statistical difference between household size and household vaccination coverage with a mean difference of 1.38(p-value, <0.001). We found a statistical difference between YF vaccination coverage among the study population and that of the national coverage (88%) with a mean difference of 0.05(p-value =<0.001). About 94% of those vaccinated were able to show proof of vaccination with certified vaccination cards. The main reason for non-vaccination was household member/s travelling out of the district during the vaccination campaign.ConclusionYF vaccination coverage was below the national vaccination coverage, but within the WHO recommended threshold in obtaining herd immunity. The catch-up vaccination targeting hard-to-reach nomadic communities was necessary, in order to reduce likelihood of future outbreaks in these groups. Where resources allow, proactive monitoring of vaccine coverage and catch-up campaigns can help countries to meet 2026 international targets for YF elimination.